Here’s What Getting a Skin Patch Test Is Really Like

A few months ago, I got hit with what my dermatologist called a “pretty severe” allergic reaction: The lower half of my face was hot to the touch and as red as a stop sign. And if that wasn’t enough, annoying little pustules were scattered across my jawline. To put it bluntly, I was miserable.

After some prescription-grade hydrocortisone cream, oral antibiotics, and a little time (10 days, to be exact), my face eventually went back to normal. But still, I couldn’t help but wonder what caused that sudden and unprecedented rash. I hadn’t added any new products to my routine, and I’m not prone to reactions like that.

I’d thought about getting a skin patch test before and knew I probably needed one to get some answers. So, I reached out to Schweiger Dermatology Group to schedule one. Here’s a day-by-day rundown of the full experience—and what I learned about my sensitive skin.

What does a skin patch test do?

A skin patch test can help ID which (if any) topical ingredients you’re allergic to, says Susanna Silverman, MD, the board-certified allergist who performed my patch test (for free) at Schweiger Dermatology Group in New York City.

Here’s how it works: During the first of three appointments, a dermatologist or allergist covers your back with rows of tiny stickers that contain different allergens—including metals (like nickel), natural oils (like tea tree and ylang-ylang), and common skin care ingredients (fragrances, for example). A patch test only tests for contact allergens, or things that physically touch your skin—not airborne or food allergens, like pet dander or tree nuts.

You keep these stickers on your back for two days—during which you can’t sweat excessively (so no exercising) or shower—and then return to your provider to have them removed. Your doctor will examine your skin during this second appointment but, because some negative reactions can take a few days to show up, you’ll also come back two days later for a final assessment. At the end of the five-day experience, you’ll walk away with a list of what, if any, substances you’re allergic to.

According to Dr. Silverman, this analysis is a great way to “identify triggers for inflamed rashes caused by eczema.” The most common form of this condition is called atopic dermatitis, which usually looks like dry, inflamed patches of skin that are very itchy. (Experts don’t fully understand what causes atopic dermatitis, but genetics and environmental factors like climate and exposure to certain allergens can play a role.) There are other types of eczema too: Contact dermatitis (what I was dealing with) happens when your skin becomes irritated after reacting to a specific trigger—either an allergen (in the case of allergic contact dermatitis) or irritant (irritant contact dermatitis).

Health insurance will often cover some, if not all, of a skin patch test, “but out-of-pocket costs, if you don’t have insurance, can range from a few hundred dollars to $1,000,” Dr. Silverman says.

The day-by-day breakdown of my skin patch test experience

Naturally, my top priority was getting an answer to what the hell happened to my face. But also, I was hoping a patch test could tell me if any of the products in my rotation were causing parts of my face to turn red. (Even before the horrible rash, I’d notice my skin getting a bit tender or itchy when I used certain “actives.”) So, without further ado, let me walk you through exactly how my patch test went.

Day 1

During my first appointment, a physician assistant applied 80 patches of different allergens all over my back and covered them with hypoallergenic tape.

Dr. Silverman emphasized that it was really important for me not to scratch, shower, or sweat so the patches would stay put until my follow-up appointment in two days. I also read online that it’s common to feel unbearably itchy when you’re taped up for this test, so I arranged to work from home for the week, just in case. My back definitely felt stiff and tight (making it difficult to bend or move freely—which was annoying). But the irritation ended up being pretty manageable overall.

Day 2

I braced myself for a full day of discomfort (like I said, I had heard horror stories)—but, to my surprise, everything was fine. Only one part of my upper back (where I ended up having an allergic reaction) was slightly itchy, as if I had a mosquito bite. Other than that, I sailed through the day feeling like my usual self—except for the whole no-showering situation.